Conventional four-wheeled land vehicles depend on contact with the ground for traction. When such a vehicle travels around a curve in the road, traction may decrease on some or all of the wheels. If a suitable centripetal force is not supplied by gravity, friction, and the road against the wheels, and not communicated effectively to act on the center of mass of the vehicle, the vehicle may roll away from the center of curvature of the curve in the road. Even the beginning of a rolling motion can be hazardous at least because traction may be unevenly distributed and/or reduced, compounding the problem of supplying a suitable centripetal force.
The driver of a conventional two-wheeled vehicle may shift the center of mass of the combination of the driver and the vehicle to bank the vehicle and its wheels toward the center of curvature to reduce the likelihood of rolling. The same is not true for conventional three- and four-wheeled vehicles. Conventional three- and four-wheeled vehicles generally include systems that bias each wheel against the road for improved traction over rough roadway. These biasing systems generally inhibit further improvement of cornering capability by the driver.
Systems have been proposed that hydraulically counteract body roll in three- and four-wheeled land vehicles. Hydraulic force is used to reposition the mass of the body and/or to counteract the wheel biasing systems.
Without the present invention vehicle cornering capability will continue to be limited. A substantial risk of unstable conditions persists for vehicles that are capable of speeds while not cornering that are far greater than safe speeds while cornering.